


Role Reversal

by banbanabas



Category: Undertale (Video Game)
Genre: Alphynecentric, F/F, Gillplay, I FEEL FILTHY WRITING THAT OH GOSH, alphys gets gutsy and undyne gets into it, that's all I'm gonna say, this is the closest i will ever get to actual smut
Language: English
Status: Completed
Published: 2015-11-29
Updated: 2015-11-29
Packaged: 2018-05-04 00:38:26
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,239
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5313257
Author URL: https://archiveofourown.org/users/banbanabas/pseuds/banbanabas
Summary: <blockquote class="userstuff">
              <p>“L-look, I know I’m not v-very good at taking charge, but I just want you to know how much you matter to me, okay?” Alphys moved the claw at Undyne’s collarbone to the side of her neck. “I might g-get nervous, so if you–” She ended the sentence right there. In fact, she no longer cared to think about finishing that sentence.</p>
<p>Because right then, Undyne let out a moan that shocked them both.</p>
<p>(Alternatively: Undyne finds out she's really into Alphys touching her gills.)</p>
            </blockquote>





	Role Reversal

**Author's Note:**

> written for a prompt on my tumblr (fishlizardweeb.tumblr.com): "kink ;3"
> 
> this was originally meant to be a short drabble. as you can see, i got a little carried away...
> 
> ALSO: this fic has bEEN MADE INTO A COMIC???? AHHHHHH! illustrated by the amazing zwiebelprinz . tumblr . com  
> Here's the first pages: http://zwiebelprinz . tumblr . com/post/134809490421/ok-here-we-go-the-first-two-pages-of-role  
> Zwiebel's also selling a booklet of alphyne content (her art, including this comic, and some of my fics :3) on her tumblr!! a link to that right here: http://zwiebelprinz . tumblr . com/post/139983052826/zwiebelprinz-zwiebelprinz-due-to-the-change
> 
> ALSO AGAIN: THE COMIC HAS A VOICEOVER OH MY G O O D N E S S.......... voice acting by the lovely and talented plumcid . tumblr . com  
> Here's the link to THAT sin: http://plumcid . tumblr . com/post/137929026485/before-in-the-underground-the-couch-in-front-of
> 
> thank you so much for those, both of you..... omg...............

Before, in the Underground, the couch in front of the TV had been their haven for anime-watching and not much else. The scene hadn’t changed much after they reached the surface: Undyne and Alphys spent most nights in their usual spot while animated shows dominated the screen, but if one was looking for them, there were noticeable differences in their routine. Namely, the two weren’t always so focused on the TV anymore.

Undyne kissed Alphys lightly on the snout, enticing a giggle from the small, reptilian woman. She placed her hands on either side of her face then and _really_ kissed her, not just a peck but something deeper, and Alphys pressed back just as strongly. Smiling against her girlfriend’s lips, Undyne snaked one arm around Alphys’s waist to pull her in closer, but before Undyne could get her further than her lap, Alphys placed a claw against Undyne’s chest and shook her head.

“Nuh-uh,” Alphys murmured. “You don’t have to take the lead all the time, y-you know.” Undyne grinned, her eye squinting knowingly at Alphys.

“Hm? You wanna start something?” she asked with a smirk. Alphys flushed, but she kept her eyes fixed on Undyne’s as she, in turn, grinned.

“Maybe.” She placed a hand against Undyne’s jaw and trailed a claw to her chin. Undyne suppressed a shudder as that claw continued down her throat and paused where her neck met her collarbone. “You’re really good at leading. The Royal Guard, writing me that l-letter to confess your feelings... The kiss on the beach.” Alphys leaned back and touched Undyne’s shoulder gently with her other hand. “And you’re really passionate about all of it.” Her courage wavered, then; Undyne noticed her looking away before she dared to return her gaze to Undyne’s. “But you said that’s what you liked about me, too. That I’m passionate.” Alphys gave a genuine but shy smile at that. “So I wanted that to translate to... T-to this.”

Undyne’s eyebrows rose near her hairline. “This?”

With a tiny, choked noise, she closed her eyes and shook her head minutely. “T-this. You. How much I care about you.”

“Oh.” Undyne felt heat rushing to her cheeks. Alphys opened her eyes again but trained them on the couch cushions.

“L-look, I know I’m not v-very good at taking charge, but I just want you to know how much you matter to me, okay?” Alphys moved the claw at Undyne’s collarbone to the side of her neck. “I might g-get nervous, so if you--” She ended the sentence right there. In fact, she no longer cared to think about finishing that sentence.

Because right then, Undyne let out a moan that shocked them both.

“Oh, my God,” she sputtered, quickly clapping a hand over her mouth. “I. Uh. Oh.” Alphys stared with a puzzled expression.

“Um, w-what happened? Did I do something?”

This time, Undyne was the one that had to look away. “Yeah, ah, my gills are pretty sensitive. Uh, a lot more sensitive than I remember,” she said. Alphys’s eyes widened, focusing on the red, membranous tissue inches from her claw.

“In a good way or bad way?”

Undyne dropped the hand from her mouth back to the couch. “A... Good way.” Alphys made a thoughtful humming noise. Undyne opened her mouth to speak again, but Alphys chose that moment to ghost her fingers over her gills; a surprised gasp escaped Undyne’s lips instead. Undyne returned the hand to her mouth, pressing a fist against her lips to keep herself from making more noises as Alphys continued the careful movements at her neck.

“That’s good?” she whispered. Undyne nodded shakily, and Alphys laughed once, quietly. “Okay. G-good.” The fingers traveled up to her jawline and back down past the membrane, sending jittery shivers all throughout Undyne’s body. She couldn’t stop herself from jerking a little at the sensation. “You still okay?” Another shaky nod, another giggle.

For all her usual bravado and confidence, Undyne found she couldn’t tear her eyes from the couch cushion she’d focused on before. It was a bit scary being so vulnerable, but she trusted Alphys. There was no way Alphys would hurt her. Besides, the feeling she got when Alphys touched her neck was a little... Too good to pass up.

Right then, Alphys drifted the hand at Undyne’s shoulder up to her neck so that both hands brushed her gills simultaneously. Undyne swallowed a whine, but she couldn’t hold back the shiver that made her shake head to toe. The hands kept moving against her neck, finding a rhythm, and Undyne could do nothing but melt wordlessly into the cushions beneath her. Her head lolled back, too, which was a blessing and a curse because it exposed even more of her neck. If she’d had her eye open, she would have seen Alphys widen her own eyes in shock and then narrow them in realization.

Undyne nearly leaped from the couch when she felt Alphys’s lips against the underside of her gills. “Oh, my _God_ , Alphys,” she muttered past her clenched fist. Her other hand had, of its own volition, gotten rather tangled in the back of Alphys’s shirt, and to her surprise she found she was pulling Alphys closer. Good God, this was embarrassing and scary and... And... Oh, she had to be honest, really, _really_ hot.

Undyne would need to think about this later.

But that was for later, definitely, because Alphys had started pressing firmer kisses against the gills on one side of her neck while her palm lightly brushed the other side, and some insanely high-pitched keening noise was coming from Undyne’s throat that she _had_ to stop but just couldn’t, couldn’t, couldn’t. Alphys hummed a laugh into her neck. The vibrations sent electricity down her spine and through her limbs, and even with that hand covering her mouth, she found she was whispering, “Oh God” and “Alphys please” over and over like a mantra.

This continued for who knows how long, Undyne didn’t know and didn’t care, but when she felt the touch of teeth against the sensitive frills, she couldn’t take it anymore. Her whole body shaking, she tugged a little at the back of Alphys’s shirt until she removed herself from Undyne’s neck. Then she kissed the woman in her lap ferociously, both hands cupping her face, Alphys’s arms wrapped around her shoulders, and at some point they flopped over in such a way that Alphys was laying on top of Undyne. When they came back for air, Alphys was looking down at her with so much emotion in her eyes that Undyne nearly choked again.

“Was that okay?” she asked. Undyne barked a nervous laugh.

“ _Was that okay_?” Undyne repeated incredulously. “I’m a freaking _mess_ and you’re asking if that was _okay_! Ha! Ha ha! Ha ha _ha ha ha_!” Alphys just smiled and shook her head.

“I’m guessing that’s a yes.” Undyne rolled her eyes, instigating another chuckle from Alphys, who then drooped over to lay against Undyne’s chest. They stayed like that, just breathing, Undyne getting herself back under control. Eventually, Alphys murmured, “Thank you for letting me do this.”

Undyne rubbed circles onto her girlfriend’s back, a smirk curling onto her lips. “Anytime, love. I should be the one thanking you, anyway.” Alphys snorted but snuggled closer. Undyne wrapped her arms around the smaller woman in a gentle embrace. “Love you, Alphys.”

“Love you, Undyne.”


End file.
